Core C - Abstract The Hemostasis and Thrombosis In Vivo Core (Core C) will serve as a resource for all projects that include animal studies. The Core will provide the resources and expertise to facilitate the design, execution and interpretation of several thrombosis models. Among the models included are: 1) FeCl3 or rose Bengal-induced injury of the mouse carotid artery in which thrombus formation is monitored by measuring blood flow through the carotid artery using a Doppler flow probe; 2) Laser, micropuncture, or rose Bengal-induced injury in the cremaster muscle microcirculation visualized in real-time by intravital microscopy; 3) laser, FeCl3 or rose Bengal-induced injury of mouse mesenteric arteries or veins visualized by intravital microscopy; 4) inferior vena cava stasis- or stenosis-induced venous thrombosis; and 5) the mouse tail bleeding assay. A detailed description of each of these models including the molecular mechanisms involved and specific advantages of each is included in the description of Core C provided in this proposal. The physical resources necessary to conduct these studies (including the Doppler flow probe setup and confocal intravital microscopy system) are already in place. The core director, Dr. Timothy Stalker, has extensive experience performing in vivo thrombosis studies and will serve as a resource to all project investigators. In addition to standard hemostasis and thrombosis models, the core will also collaborate with project investigators to develop more advanced imaging techniques and additional hemostasis/thrombosis models that may then be utilized by all project investigators to advance their projects and increase our understanding of the mechanisms regulating hemostasis and thrombosis in vivo.